Sharon Supon, owner of the Zenobia bookstore cafe in Concord, Calif., says that the concept may have evolved because "the only way to compete against the large bookstore chains is to offer something extra." Zenobia is primarily a bookstore, and Ms. Supon considers the pastry-and-beverage bar merely "an auxiliary to my books, a service to my customers."

Other bookstore-cafes put more or less emphasis on the gastronomic menu. Kramer Books and Afterwords -- The Cafe, in Washington's trendy DuPont Circle, has more of a literary coffeehouse atmosphere than its newer sister, The Brasserie, on Eye Street in Washington, where customers concentrate more on eating than on reading.

Most of the bookstore cafes, including the Book Plate in San Francisco, make more profit from food than from books. Dick Chase, owner of The Bookstore Cafe in Boston. Market, says food accounts for two-thirds of his sales.

Don't confuse the bookstore cafe concept with restaurants outfitted with library decor, or a college hangout where old books and magazines lie scattered around. The new establishments are bona fide, working bookstores.

"It's not a student kind of place," Mr. Chase says. "We don't serve your normal hamburger. It is a kind of European atmosphere, an indoor/outdoor cafe feeling, with the bookshelves taking the place of the streets."

Lauren, a Harvard University student who works part-time as a waiter at The Bookstore Cafe on Newbury Street in Boston, says that people feel freer to eat alone there, especially because they are able to read at the tables. Customers can browse a few chapters of a best seller that they are not yet certain they want to buy. Yet, say bookstore cafe owners, customers do not abuse the opportunity to read a book for free while they eat. "People seldom sit down and read a whole book without buying it," Ms. Supon says.

What about smudging Haagen Dazs ice cream on Page 14? Lauren says that isn't much of a problem.

"People are careful," he says. Chase confirms that observation. "We haven't run into one single instance of people spilling on the books."

The cafes make up for the slow customer turnover by charging premium prices for quality food. Waiters sense that the clientele comes to the cafes precisely for the unhurried atmosphere, the exposed brick walls, the caned chairs.

And they pay for it.

The Harvard Bookstore Cafe and Zenobia both garner a fair share of author's autograph-signing parties, since food and drink can help establish a more festive atmosphere than an ordinary bookstore.

Whether these new crossbreeds will become modern-day meeting places to swap ideas and concepts -- like Boston's Old Corner Bookstore 150 years ago -- only time can tell.